A gas turbine engine generally includes a fan and a core arranged in flow communication with one another. Additionally, the core of the gas turbine engine general includes, in serial flow order, a compressor section, a combustion section, a turbine section, and an exhaust section. In operation, air is provided from the fan to an inlet of the compressor section where one or more axial compressors progressively compress the air until it reaches the combustion section. Fuel is mixed with the compressed air and burned within the combustion section to provide combustion gases. The combustion gases are routed from the combustion section to the turbine section. The flow of combustion gases through the turbine section drives the turbine section and is then routed through the exhaust section, e.g., to atmosphere.
The combustion section of the gas turbine engine must withstand extremely high operating temperatures. For example, the ignited air/fuel mixture in the combustor can reach temperatures in excess of about 3500° F. (about 1930° C.). Due to these high temperatures, heat shields (e.g., deflector plates) are typically placed around each air/fuel mixer to protect other combustor components from the ignited air/fuel mixture. Deflector plates may be fabricated from various materials that are preferably characterized by mechanical and environmental properties that are particularly well suited for its use as a heat shield in the combustor environment of a gas turbine engine.
More commonly, non-traditional high temperature materials, such as ceramic matrix composite (CMC) materials, are being used as structural components within gas turbine engines. For example, given the ability for CMC materials to withstand relatively extreme temperatures, there is particular interest in replacing components within the combustion section of the gas turbine engine with CMC materials. More particularly, one or more heat shields of gas turbine engines are more commonly being formed of CMC materials. In addition, or alternatively, combustor components may receive thermal barrier coatings to ensure improved durability in high temperature environments.
Even with the advance of high temperature materials, combustor components that are closest in proximity to the combustion flame are still at risk of premature degradation. Uniform, non-varying combustion in the combustion chamber is desirable to improve engine performance and efficiency. In this regard, the components of the combustion chamber are carefully designed to ensure that injected fuel is properly mixed with compressed air to achieve the optimal air/fuel ratio, the entire air-fuel mixture is uniformly distributed within the combustion chamber, and complete combustion of the mixture is achieved. Notably, while improved fuel distribution improves engine efficiency, it may also result in the combustion flame remaining closer to the dome portion of the combustor, which may thereby be heated beyond desirable levels.
Accordingly, a combustor for a gas turbine engine capable of evenly distributing and optimally combusting the air-fuel mixture would be useful. In addition, a combustor that improves flow stability in the combustor while ensuring combustor components do not experience unacceptable temperatures, thus improving the operational capability and durability of the engine, would be particularly beneficial.